Robust Direct Torque Control of An Adjustable Speed Sensorless Induction Machine Drive Using A PI Predictive Controller

다국어 초록 (Multilingual Abstract)

A Direct torque and flux control design for a sensorless induction motor, following a sliding mode observer is presented. In this control scheme, the torque error signal and the reference amplitude of the stator flux vector are delivered to a PI predictive controller. The predictive controller also uses information on the amplitude and position of the actual stator flux vector and measured current to determine the voltage command vector for space<br/>
vector modulation (SVM). Using the fifth order model of three-phase induction machines in a stationary two axes reference frame, a sliding- mode (SM) observer is developed based on equivalent control concept in order to estimate the rotor speed and rotor time constant simultaneously. The stability of SM observer is proved by Lyapunov theory. In addition, a simple Lyapunov-based estimator is also used for on-line detecting of the stator resistance. Moreover, a composite SM controller is employed that combines nominal linear quadratic feedback control (LQC) and a SM contyrol. The composite speed controller, makes the drive system states follow the nominal trajectories in spite of parameter uncertainties and external load torque disturbance. The effectiveness of the proposed control scheme is verified by computer simulation.

목차 (Table of Contents)

• Abstract
  
• Ⅰ. INTRODUCTION
  
• Ⅱ. INDUCTION MOTOR MODEL
  
• Ⅱ. IM DTC-SVM SCHEME
  
• Ⅳ. SPEED CONTROLLER
  
• Ⅴ. SLIDING MODE OBSERVER
  
• Ⅵ. SYSTEM SIMULATION
  
• Ⅶ. CONCLUSION
  
• REFERENCES